<template>
    <div>
        <!-- 面包屑导航区域 -->
        <el-breadcrumb separator-class="el-icon-arrow-right">
            <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
            <el-breadcrumb-item>商品管理</el-breadcrumb-item>
            <el-breadcrumb-item>参数列表</el-breadcrumb-item>
        </el-breadcrumb>

        <!-- 卡片视图区域 -->
        <el-card>
            <!-- 头部警告区域 -->
              <el-alert show-icon title="注意：只允许第三级分类设置相关参数!" 
              type="warning" :closable="false"></el-alert>

              <!-- 选择商品分类区域 -->
              <el-row class="cat_opt">
                  <el-col>
                      <span>选择商品分类:</span>
                      <!-- 选择商品分类的级联选择框  -->
                      <el-cascader expand-trigger="hover" v-model="selectedCateKeys" :options="catelist" 
                      :props="cateProps" @change="handleChange" clearable></el-cascader>
                  </el-col>
              </el-row>

              <!-- tab页签区域 -->
                <el-tabs v-model="activeName" @tab-click="handleTabClick">
                    <!-- 添加动态参数的面板 -->
                    <el-tab-pane label="动态参数" name="many">
                        <!-- 添加参数按钮 -->
                        <el-button type="primary" size="mini" 
                        :disabled="isBtnDisabled" @click="addDialogVisible = true">添加参数</el-button>
                        <!-- 动态参数表格 -->
                        <el-table :data="manyTableData" border stripe>
                            <!-- 展开行 -->
                            <el-table-column type="expand">
                                <template slot-scope="scope">
                                    <!-- 循环渲染Tag标签 -->
                                    <el-tag v-for="(item,i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i,scope.row)">
                                        {{item}}
                                    </el-tag>
                                    <!-- 输入的文本框 -->
                                    <el-input class="input-new-tag" v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                                    ref="saveTagInput" size="small" 
                                    @keyup.enter.native="handleInputConfirm(scope.row)" @blur="handleInputConfirm(scope.row)">
                                    </el-input>
                                    <!-- 添加按钮 -->
                                    <el-button v-else class="button-new-tag" 
                                    size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                                </template>
                            </el-table-column>
                            <!-- 索引列 -->
                            <el-table-column type="index"></el-table-column>
                            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
                            <el-table-column label="操作">
                                <template slot-scope="scope">
                                    <el-button size="mini" type="primary" icon="el-icon-edit" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                                    <el-button size="mini" type="danger" icon="el-icon-delete" @click="removeParams(scope.row.attr_id)">删除</el-button>
                                </template>
                            </el-table-column>
                        </el-table>
                    </el-tab-pane>
                    <!-- 添加静态属性的面板 -->
                    <el-tab-pane label="静态属性" name="only">
                        <!-- 添加属性按钮 -->
                        <el-button type="primary" size="mini" 
                        :disabled="isBtnDisabled" @click="addDialogVisible = true">添加属性</el-button>
                        <!-- 静态属性表格 -->
                        <el-table :data="onlyTableData" border stripe>
                            <!-- 展开行 -->
                            <el-table-column type="expand">
                                <template slot-scope="scope">
                                    <!-- 循环渲染Tag标签 -->
                                    <el-tag v-for="(item,i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i,scope.row)">
                                        {{item}}
                                    </el-tag>
                                    <!-- 输入的文本框 -->
                                    <el-input class="input-new-tag" v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                                    ref="saveTagInput" size="small" 
                                    @keyup.enter.native="handleInputConfirm(scope.row)" @blur="handleInputConfirm(scope.row)">
                                    </el-input>
                                    <!-- 添加按钮 -->
                                    <el-button v-else class="button-new-tag" 
                                    size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                                </template>
                            </el-table-column>
                            <!-- 索引列 -->
                            <el-table-column type="index"></el-table-column>
                            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
                            <el-table-column label="操作">
                                <template slot-scope="scope">
                                    <el-button size="mini" type="primary" icon="el-icon-edit" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                                    <el-button size="mini" type="danger" icon="el-icon-delete" @click="removeParams(scope.row.attr_id)">删除</el-button>
                                </template>
                            </el-table-column>
                        </el-table>
                    </el-tab-pane>
                </el-tabs>
        </el-card>

        <!-- 添加参数的对话框 -->
        <el-dialog :title="'添加' + titleText" :visible.sync="addDialogVisible" width="50%" @close="addDialogClosed">
            <!-- 添加参数的对话框 -->
            <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
                <el-form-item :label="titleText" prop="attr_name">
                    <el-input v-model="addForm.attr_name"></el-input>
                </el-form-item>
            </el-form>
            <span slot="footer" class="dialog-footer">
                <el-button @click="addDialogVisible = false">取 消</el-button>
                <el-button type="primary" @click="addParams">确 定</el-button>
            </span>
        </el-dialog>

        <!-- 修改参数的对话框 -->
        <el-dialog :title="'修改' + titleText" :visible.sync="editDialogVisible" width="50%" @close="editDialogClosed">
            <!-- 添加参数的对话框 -->
            <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
                <el-form-item :label="titleText" prop="attr_name">
                    <el-input v-model="editForm.attr_name"></el-input>
                </el-form-item>
            </el-form>
            <span slot="footer" class="dialog-footer">
                <el-button @click="editDialogVisible = false">取 消</el-button>
                <el-button type="primary" @click="editParams">确 定</el-button>
            </span>
        </el-dialog>
    </div>
</template>

<script>
export default {
    data(){
        return{
            //商品分类列表
            catelist: [],
            //级联选择框的配置对象
            cateProps:{
                value:'cat_id',
                label:'cat_name',
                children:'children'
            },
            //级联选择框双向绑定到的数组
            selectedCateKeys: [],
            //被激活的页签的名称
            activeName: 'many',
            //动态参数的数据
            manyTableData: [],
            //静态参数的数据
            onlyTableData: [],
            //控制添加对话框的显示与隐藏
            addDialogVisible: false,
            //添加参数的表单数据对象
            addForm: {
                attr_name: ''
            },
            //添加表单的验证规则对象
            addFormRules:{
                attr_name: [
                    { required:true, message:'请输入参数名称',trigger:'blur' }
                ]
            },
            //控制修改对话框的显示与隐藏
            editDialogVisible : false,
            //修改的表单数据对象
            editForm:{},
            //修改表单的验证规则对象
            editFormRules:{
                attr_name: [
                    { required:true, message:'请输入参数名称',trigger:'blur' }
                ]
            },
            //控制按钮与文本框的切换显示
            inputVisible : false,
            //文本框中输入的内容
            inputValue: ''
        }
    },
    created() {
        this.getCateList()
    },
    methods: {
        //获取所有的商品分类
        async getCateList(){
            const {data:res} = await this.$http.get('categories')
            if(res.meta.status !== 200){
                return this.$message.error('获取商品分类失败!')
            }
            this.catelist = res.data;
            console.log(this.catelist);
        },
        //级联选择框选中项变化，会触发这个函数
        handleChange(){
            this.getParamsData()
        },
        //tab页签点击事件的处理函数
        handleTabClick(){
            console.log(this.activeName);
            this.getParamsData()
        },
        //获取参数的列表数据
        async getParamsData(){
            //证明选中的不是三级分类
           if(this.selectedCateKeys.length !==3){
               this.selectedCateKeys = []
               this.manyTableData = []
               this.onlyTableData = []
               return
           }
           //证明选中的是三级分类
           console.log(this.selectedCateKeys);
           //根据所选分类的Id和当前所处的面板，获取对应的参数
           const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes`
           ,{params:{sel:this.activeName}})

           if(res.meta.status !== 200){
               return this.$message.error('获取参数列表失败！')
           }
           
           res.data.forEach(item => {
               item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
               //控制文本框的显示与隐藏
               item.inputVisible = false
               //文本框中输入的值
               item.inputValue = ''
           })
            console.log(res.data);
           if(this.activeName === 'many'){
               this.manyTableData = res.data
           }else{
               this.onlyTableData = res.data
           }
        },
        //监听添加对话框的关闭事件
        addDialogClosed(){
            this.$refs.addFormRef.resetFields()
        },
        //点击按钮，添加参数
        addParams(){
            this.$refs.addFormRef.validate(async valid =>{
                if(!valid) return
                const {data:res} = await this.$http.post(`categories/${this.cateId}/attributes`,{
                    attr_name: this.addForm.attr_name,
                    attr_sel: this.activeName
                })
                if(res.meta.status !== 201){
                    return this.$message.error('添加参数失败!')
                }
                this.$message.success('添加参数成功!')
                this.addDialogVisible = false
                this.getParamsData()
            })
        },
        //点击按钮展示修改对话框
        async showEditDialog(attrId){
            //查询当前参数的信息
            const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes/${attrId}`,{
                params:{ attr_sel:this.activeName }
            })
            if(res.meta.status !== 200){
                return this.$message.error('获取参数信息失败!')
            }
            this.editForm =res.data
            this.editDialogVisible = true
        },
        //重置修改表单
        editDialogClosed(){
            this.$refs.editFormRef.resetFields()
        },
        //点击按钮，修改参数信息
        editParams(){
            this.$refs.editFormRef.validate(async valid =>{
                if(!valid) return
                const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,{
                    attr_name: this.editForm.attr_name,
                    attr_sel: this.activeName
                })
                if(res.meta.status !== 200){
                    return this.$message.error('修改参数失败!')
                }
                this.$message.success('修改参数成功!')
                this.getParamsData()
                this.editDialogVisible = false
            })
        },
        //根据Id删除对应的参数项
        async removeParams(attrId){
            const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', 
            {
                confirmButtonText: '确定',
                cancelButtonText: '取消',
                type: 'warning'
            }).catch(err => err)

            //用户取消了删除的操作
            if(confirmResult !== 'confirm'){
                return this.$message.info('已取消删除!')
            }

            //删除的业务逻辑
            const {data:res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attrId}`)
            if(res.meta.status !== 200){
                return this.$message.error('删除参数失败!')
            }
            this.$message.success('删除参数成功')
            this.getParamsData()
        },
        //文本框失去焦点，或摁下了Enter都会触发
        handleInputConfirm(row){
            if(row.inputValue.trim().length === 0){
                row.inputValue = ''
                row.inputVisible = false
                return
            }
            //如果没有return，则证明输入的内容，需要做后续处理 
            row.attr_vals.push(row.inputValue.trim())
            row.inputValue = ''
            row.inputVisible = false
            //需要发起请求，保存这次操作
            this.saveAttrVals(row)
        },
        //将对attr_vals的操作 保存到数据库
        async saveAttrVals(row){
            //需要发起请求，保存这次操作
            const {data:res} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`,{
                attr_name:row.attr_name,
                attr_sel:row.attr_sel,
                attr_vals:row.attr_vals.join(' ')
            })
            if(res.meta.status !== 200){
                return this.$message.error('修改参数项失败!')
            }
            this.$message.success('修改参数项成功!')
        },
        //点击按钮，展示文本输入框
        showInput(row){
            row.inputVisible = true;
            //让文本框自动获取焦点
            //$nextTick 方法的作用，就是当页面上元素被重新渲染之后，才会指定回调函数中的代码
            this.$nextTick(_ => {
                this.$refs.saveTagInput.$refs.input.focus();
            });
        },
        //删除对应的参数可选项
        handleClose(i,row){
            row.attr_vals.splice(i,1)
            this.saveAttrVals(row)
        }
    },
    computed:{
        //如果按钮需要被禁用，则返回true，否则返回false
        isBtnDisabled(){
            if(this.selectedCateKeys.length !== 3){
                return true
            }
            return false
        },
        //当前选中的三级分类的Id
        cateId(){
            if(this.selectedCateKeys.length === 3){
                return this.selectedCateKeys[2]
            }
            return null
        },
        //动态计算标题的文本
        titleText(){
            if(this.activeName === 'many'){
                return '动态参数'
            }
            return '静态属性'
        }
    }
}
</script>

<style lang="less" scoped>
.cat_opt{
    margin: 15px 0;
}
.el-tag{
    margin:10px
}
.input-new-tag{
    width: 120px;
}
</style>